Freeze Tolerant Water Azeotrope Radiators

The “Freeze Tolerant Water Azeotrope Radiator” is a heat rejection technology that can survive the 14 day lunar night without trace heaters or other energy sources. Its purpose is to reject multi-kilowatt thermal loads (10’s to 100’s of kWt) during hot operations plus be able to survive a lunar night anywhere on the moon whether operating or in standby mode. Combining large deployable radiator panels with embedded water azeotrope heat pipes that allow flexure at the joints provides a system which can be stowed and mobilized or deployed and operational with the ability to survive freeze and thaw cycles as needed depending on the mission and fault tolerance of its parent system. This freeze tolerant and mobile radiator subsystem can integrate with power generation and distribution, mobility assets, and In-Situ resource processing plants. It can be designed to operate on the moon or Mars with and without gravity assistance.  This is achieved by utilizing the unique properties of water azeotropes that turn to a slush consistency when frozen which greatly reduces structural stresses. This allows the heat pipe pressure vessel to be designed with thin walls that increase heat transfer, reduce mass, and allow thin walled bellows or like structures needed for deployable operations. Phase I will focus on down selecting water azeotrope fluids, heat pipe design, and deployable radiator architecture. Subscale testing of a loop heat pipe and thermosyphon are expected to help support decisions leading to a phase II program. If selected, phase II will include a deployable multi-panel radiator in a thermal vacuum chamber that demonstrates freeze thaw operations from 400K (TBD) down to 80K and back for multiple cycles. Phase III will be target a lunar lander demonstration. Markets for this technology will include all moon to Mars systems that require freeze tolerant heat rejection with two phase fluids.  

The freeze tolerant water azeotrope radiator technology has many NASA applications due to its unique capability to survive the lunar night and provide multi-kilowatt heat transfer and heat rejection. These radiators can be used to reject heat from a source to a deep space/surface sink or be directed toward lunar assets requiring heat during the night (heated garage) when used with nuclear power. Both large and smaller scale water azeotrope radiator technology being proposed will have the ability to autonomously stow and deploy depending on the heat rejection demands. This offers 100% turn down ratios that can literally be frozen when not in use and start back up when heat is returned. Passively going from a frozen 0 Watt state to a multi-kilowatt heat rejection state autonomously has never been accomplished. These applications include fission surface power heat rejection, human habitat heat rejection/addition, asset storage heat addition, power distribution heat rejection, rover and lander heat rejection/addition, in-situ resource processing rejection/addition, and ice melting. Commercial applications for this technology will include both terrestrial and space. Private companies like Intuitive Machines and Firefly Aerospace are making great progress in lunar exploration with their landers. This radiator technology could easily be adapted for lander or payload heat rejection. Like above NASA applications, private companies will develop and send non-government funded systems to the lunar surface that will need to survive the lunar night. We’ve seen the advent of commercial nuclear radioisotope heat sources being developed by companies like ZENO Technologies that will allow a new nuclear heat source to help lunar assets survive the night. Spreading heat form the radioisotope heat source to larger areas will require passive heat pipe radiators to keep systems like electronics from dropping below survivability temperatures without the need for pumps. Terrestrial usage of water azeotropes could have the most influential impact due to its inherent non-toxic chemistry. The ecological and environmental impacts of switching out current refrigerants with water azeotropes is substantial and could become a multi-billion dollar industry on its own.

This is a mature technology (TRL 7+) — the realistic path in is usually NASA's Technology Transfer Program: licensing an existing NASA patent, or a Space Act Agreement to use NASA facilities/expertise directly. NASA also runs a startup licensing program with no upfront fee for companies formed to commercialize a specific NASA technology.

None of these are guaranteed paths for this specific project — TechPort itself doesn't have an "apply" button. Reaching out to the contact(s) above with a specific question is usually the fastest way to find out what's actually open.